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90                                          i*LOB,A INDICA.                          [dnonacea.
tion given by Blume himself. Throughout the Order the shape of the petals ap-
pears to afford characters of great importance, and the facility with which it can
he determined makes it of great practical utility. The particular modifications are
readily recognized, and have for the most part been already indicated; others will he
specially noticed under the different genera.
As an accessory character the inflorescence is deserving of attention, since it will
often be found that its different modifications correspond with generic groups. The
inflorescence of Anowcea is generally definite and terminal, but very often, by the
continuance of the growth of the axillary bud, the flowers become leaf-opposed. IVe-
quently the leaves on the flower-bearing branch are reduced to mere bracts or scales,
in which case we have axillary cymes. These are occasionally so far reduced as to
hear only one flower, with several empty bractlets at the base of the peduncle; but
truly axillary and solitary flowers are very rare,
The nature of the fruit appears to bear less relation to the natural groups than
any of the characters enumerated above. The number of ovaries which ripen their
seeds, and the number of seeds which are developed, vary much. Many-seeded fruits
occur in the same capitnlum with one-seeded ones in many Uvaria and Melodora.
In Unona the many-jointed pods are frequently reduced to one joint. Occasionally
(as in Guatteria] the shape of the seed and the nature of the testa afford good
characters, but the fruit of many species being yet unknown, the universality of this
character is still doubtful, The dry and fleshy fruit is also a very uncertain cha-
racter, as the endocarp appears to remain long dry, and at last suddenly to become
pulpy: this we have observed in several genera. We have therefore made no use of
characters derived from the fruit, except for the purpose of distinguishing species.
In distribution Anonacea arc one of the most tropical Orders. The most northern
species known is Aslmina ^ygmaa^ which is found on the southern shores of Lako
Erie, in North America. In South America they do not extend beyond 32 S. In
Africa some occur at Natal, but none in the Cape district. In the Mediterranean
province and throughout Europe they are unknown. In China a few occur as far
north as Hongkong, but none in North China or Japan. In India only one species
extends to 30 N., and in Australia one only is known further south than Moreton
Bay, namely Eupomatia, which is a native of New South Wales.
So many Anonacece are still mulescribed, and the materials which exist in her-
baria are still so imperfect, that the number of species cannot be definitely esti-
mated. A conjectural estimate way, however, be formed. We have described 123
species. Blume has enumerated 31 from Java alone; and from the materials we have
seen, we think we may safely assume that the Malayan Archipelago contains at least
as many as continental India. In Australia they are probably much less numerous,
the climate of that country being very much drier: several very interesting forms
have, however, been brought from the northern and eastern coasts of that conti-
nent, and their number will probably be hereafter considerably increased. On the
whole, we may assume the number of eastern species to be about 250. For Ame-
rica we may perhaps allow an equal number, as Yon Martius has enumerated 97
species in the Brazilian flora, and they are very numerous in equatorial America.
Prom Africa few are as yet known, but, as has been pointed out by Benthain, they
bear a very large proportion to the whole amount of the flora of western tropical
Africa, and they extend throughout the whole of the continent as far as Abyssinia,
Madagascar, and Natal 3 their number may therefore be guessed at 100; which
would make the total number of species in the Order 600.
In India the Anonacea are most abundant in the Malayan peninsula, from which
55 are known. Ceylon has about half that number, of which all but three are dif-
ferent from those of Malaya. They exhibit a marked preference for the humid pro-
vinces, and are almost entirely wanting in the drier ones. The number lessens as
we proceed northward, but they are still numerous in the forests at the base of the
Khasia mountains and in the Assam valley, Further west they rapidly diminish in
number, though a few creep along the base of the Himalaya as far as Nipal. The
forms characteristic of Ceylon and Malabar extend north along the chain of the Ghata